There was a brief discussion on this when Interjection first came out. Some people were noticing that darker skinned textures were coming out surprisingly red.
For Interjection, the solution seems to be tinkering with SSS and Translucency shades in the brown and yellow range.
forumarchive.daz3d.com: Slimer_J_Spud: in “Interjection Released” thread
Posted:Mon Dec 05, 2011 10:13 am
I think I finally got a nice render using Interjections. The video tutorial set me straight. My issue was with the pink tone on dark skin, and perhaps thanks to discussing that here, the tutorial included a sample setting with the Rob texture. I’m using Marie, and the render looks nice! I only used 2 distant lights, both with raytraced shadows.
FYI, here are my skin settings for Marie elite: Diffuse strength 100%, Diffuse color 170,170,170, Ambient off, and the all-important Subsurface color, 200,212,72. The Subsurface color is more of a bronze than the salmon pink Interjections uses by default. That’s the big thing I was missing. My test renders were done without the hair, and only took about 8 or 9 minutes. The hair made it about 2.5 hrs. The Interjections set is V4 middle, with eye setting K.
Image of Marie Elite with Interjection applied (Expression Engine won’t let us embed images from external sites at the current time, so a link’s all I could do.)
(Revisiting that thread was surprisingly useful, at this late date; I just realized that one of my characters gets blown out in Interjection because her specular maps either don’t exist or are in the wrong place. Since using Ubersurface on her makes her look like she’s got the worst case of dry skin you’ve ever seen, that’s helpful to know. But I digress.)
Interjection requires at least one light in the scene to have raytraced shadows, and preferably all of them.
For Ubersurface, what I’ve done is to take settings for darker skinned characters that use HSS and then upgrade them with the UberSurface2 Base Upgrade preset, using CTRL to make sure that textures are ignored, and that it just adds the extra options. (HSS/EHSS is a subset of Ubersurface, more or less.) You pick a body area, remove all the textures from it, then save that section as a shader. Then you can tinker with the settings colors, using those to start. The ones I have using HSS are Chablis, Rob Elite, Lee Elite, Marie Elite, and also Natasha, although I haven’t done anything with her as yet. Again, most of the tinkering is in the yellow/brown range—though I think Lee’s SSS and translucency are white, if I remember correctly; I don’t know if that was intentional or if he just doesn’t have the right settings applied.
Also, apart from Interjection, the only other character’s I’ve found with SSS maps (which you should use with SSS and Translucency to tell it where and how strong to apply) are the ones from JSGraphics/Male-M3dia/ForbiddenWhispers. Other people probably produce them, of course; I just don’t have those characters.
Hope this is helpful.